Nasson, B. (ed). Turning Points in History: Book 1: Ancient Civilisations and Global Trade. Johannesburg: STE. Randles, W. G. L. (1975). The Empire of Monomotapa: from the Fifteenth to the Nineteenth Century. Salisbury. Mambo Press. Voigt, E. A. (1983). Mapungubwe: An archaeological interpretation of an Iron Age community. Pretoria: Transvaal Museum. This list is not yet complete.